Rays trade 3B Richie Shaffer, UT Taylor Motter for three prospects

Late Friday, just ahead of the 40-man roster deadline, the Rays traded infielders Richie Shaffer and Taylor Motter to the Mariners for pitchers Dylan Thompson and Andrew Kittredge and first baseman Dalton Kelly.

The team also designated reliever Steve Geltz for assignment and released left-handed pitcher John Lamb in solidifying the roster, which you can read more about here.

Shaffer, the team's first-round pick in 2012, made his big league debut in 2015 on the heels of a big breakout season in the minors. He batted .189 and posted a .307 on-base percentage in 31 games for Tampa Bay that season with four home runs.

The former Clemson infielder did not have quite the same minor league success in 2016, but his cup of coffee was better. The 25-year-old slashed .250/.315/.438 in 54 plate appearances, mostly at the end of the season.

Like Shaffer, Motter, 27, was unable to build on previous success in 2016.

The utility player's OPS in Durham dropped 151 points from 2015 to 2016. He did earn a call-up to the big leagues in 2016 and batted .188 with a .590 OPS in 93 plate appearances.

Motter did not rejoin the Rays in September following the roster expansion, and there were some insinuations that was punishment for something, though some dispute that.

Both infielders have major league potential, but were crowding the Rays roster. Dealing them to the Mariners allowed Tampa Bay to protect two additional prospects, while stocking the farm system with a few more pieces.

Here's what the Rays gained in the trade:

Dylan Thompson

Thompson is a 20-year-old right-handed pitcher. Per Rotoworld's Chris Crawford, he dealt with arm soreness for much of the 2016 season, and Baseball America reports that he missed significant time to tend to his ailing father, who was battling cancer. He pitched just 4 2/3 innings in 2016.

In 2015, the fourth-rounder from a South Carolina high school impressed in his pro debut, striking out 25 and walking eight with a 2.36 ERA in 26 2/3 innings in the Arizona League. For his efforts, Baseball America ranked him as the 20th-best prospect in the league (BA $). Its report lauded his competitiveness and polish, noting his low-90s fastball and ability to locate and change speeds. Thompson entered the season as the team's No. 12 prospect according to BA.

Dalton Kelly

Kelly, 22, mostly played first base for Class-A Clinton in 2016, but he also spent some time in the outfield. The 6-foot-3, 180-pound lefty was a 38th-round pick out of UC Santa Barbara by the Mariners in 2015. Although he got most of his action in the field at first base, a 2014 report from Baseball America indicated he could maybe play center field (BA $), and he did steal 21 bases in 2016.

For the LumberKings, Kelly batted .283 with a .384 on-base percentage and slugged .416 with seven home runs and 30 doubles. He struck out in 20.2 percent of his plate appearances and had an 11.2 percent walk rate. His rates are actually pretty similar to Jake Bauers' when he was in the Midwest League, but Bauers did it as an 18-year-old, while Kelly was 21 most of the season.

Andrew Kittredge

The 26-year-old Kittredge was originally drafted in the 45th round in 2008, back in the olden days when the draft went 50 rounds. He did not sign, but maybe he should've. After a career at the University of Washington and Lewis-Clark State, he went undrafted and then signed with the Mariners.

Working his way through the Mariners' system, Kittredge reached Triple A for the first time in 2015 and split 2016 between Double-A Jackson and Triple-A Tacoma. Between those levels, he had a 3.50 ERA with a 27.2 percent strikeout rate and 6.1 percent walk rate. In his career, he's allowed 37 home runs in 342 2/3 innings, but after subtracting all the damage done at High Desert, the former mega-launching pad of the California League, it's just 16 in 210 2/3 innings.

He once struck out five batters in one inning, and briefly pitched for Peoria in the Arizona Fall League in 2016 alongside the Rays' AFL contingent, which is where is name may have become known among the staff.